Augmented reality precision tracking and display

ABSTRACT

Example systems, devices, media, and methods for tracking movable objects and presenting virtual elements on a display in proximity to the movable objects. Ultra-wideband (UWB) transmitters are mounted to each movable object in an environment including at least two synchronized UWB receivers. The receivers calculate current locations of movable objects. Portable electronic devices, including eyewear devices, are paired with the receivers in a network. A localization application determines a current location of each eyewear device. A rendering application presents virtual elements on a display as an overlay relative to the current movable object location and in relative proximity to the current eyewear location. The physical environment is represented by a static mesh. A time synchronized tracking application identifies moving items that are not coupled to a UWB transmitter. The rendering application presents the virtual elements on the display in accordance with the static mesh and the moving items.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.17/161,213 filed on Jan. 28, 2021, and claims priority to U.S.Provisional Application Ser. No. 63/131,961 filed on Dec. 30, 2020, thecontents of both of which are incorporated fully herein by reference.

TECHNICAL FILED

Examples set forth in the present disclosure relate to the field ofaugmented reality and wearable electronic devices, such as eyewear. Moreparticularly, but not by way of limitation, the present disclosuredescribes the display of virtual elements in proximity to movableobjects, which are tracked using ultra-wideband (UWB) technology.

BACKGROUND

Many types of computers and electronic devices available today, such asmobile devices (e.g., smartphones, tablets, and laptops), handhelddevices, and wearable devices (e.g., smart glasses, digital eyewear,headwear, headgear, and head-mounted displays), include a variety ofcameras, sensors, wireless transceivers, input systems, and displays.

Ultra-wideband (UWB) is a radio-based technology for short-range,high-bandwidth pulses for transmitting data. IEEE 802.15.4a sets forththe international technical standard for the physical layers associatedwith UWB transmissions. In the context of tracking, two or more UWBreceivers are placed in a physical space and time synchronized. UWBtransmitters attached to movable objects emit a pulse periodically. Eachreceiver timestamps the arrival of each pulse. The timestamps are usedby multilateration algorithms to compute the precise location (x, y, z)of each transmitter (on each movable object) based on the timedifference of arrival of each pulse at each receiver. The pulsetransmitters broadcast pulses over a relatively short range (e.g., up to250 meters) and operate on relatively low power (e.g., one milliwatt).

Virtual reality (VR) technology generates a complete virtual environmentincluding realistic images, sometimes presented on a VR headset or otherhead-mounted display. VR experiences allow a user to move through thevirtual environment and interact with virtual objects. Augmented reality(AR) is a type of VR technology that combines real objects in a physicalenvironment with virtual objects and displays the combination to a user.The combined display gives the impression that the virtual objects areauthentically present in the environment, especially when the virtualobjects appear and behave like the real objects.

Computer vision and AR systems continually scan all the objects in aphysical environment, both stationary and moving, without detecting theidentity of any particular object or differentiating it from otherobjects. For example, an open door is detected and scanned withoutregard for whether it is related to the same door, in a closed position,detected in a previous scan. In the current scan, the open door isidentified as a new door. Computer vision and AR systems do not maintaina continuity of identity associated with movable objects.

BRIEF DESCRIPTION OF THE DRAWINGS

Features of the various examples described will be readily understoodfrom the following detailed description, in which reference is made tothe figures. A reference numeral is used with each element in thedescription and throughout the several views of the drawing. When aplurality of similar elements is present, a single reference numeral maybe assigned to like elements, with an added lower-case letter referringto a specific element.

The various elements shown in the figures are not drawn to scale unlessotherwise indicated. The dimensions of the various elements may beenlarged or reduced in the interest of clarity. The several figuresdepict one or more implementations and are presented by way of exampleonly and should not be construed as limiting. Included in the drawingare the following figures:

FIG. 1A is a side view (right) of an example hardware configuration ofan eyewear device suitable for use in a tracking and display system;

FIG. 1B is a perspective, partly sectional view of a right corner of theeyewear device of FIG. 1A depicting a right visible-light camera, and acircuit board;

FIG. 1C is a side view (left) of an example hardware configuration ofthe eyewear device of FIG. 1A, which shows a left visible-light camera;

FIG. 1D is a perspective, partly sectional view of a left corner of theeyewear device of FIG. 1C depicting the left visible-light camera, and acircuit board;

FIGS. 2A and 2B are rear views of example hardware configurations of aneyewear device of FIG. 1A;

FIG. 3 is a diagrammatic depiction of a three-dimensional scene, a leftraw image captured by a left visible-light camera, and a right raw imagecaptured by a right visible-light camera of the eyewear device of FIG.1A;

FIG. 4 is a functional block diagram of an example tracking and displaysystem including pulse transmitters, receivers, a wearable device (e.g.,an eyewear device) and a server system connected via various networks;

FIG. 5 is a diagrammatic representation of an example hardwareconfiguration for a mobile device of the tracking and display system ofFIG. 4 ;

FIG. 6 is a functional block diagram of an example tracking and displaysystem including ultra-wideband pulse transmitters coupled to movableobjects, two ultra-wideband receivers, one or more eyewear devices, oneor more mobile devices, and a collection of database elements;

FIG. 7 is a perspective illustration of an example physical environmentshowing ultra-wideband pulse transmitters coupled to movable objects, anexample object mesh, and a portion of a static mesh; and

FIG. 8 is a perspective illustration of an example virtual elementpresented near a movable object on an eyewear display.

DETAILED DESCRIPTION

Various implementations and details are described with reference toexamples, including an example system for tracking movable objects anddisplaying virtual elements in relative proximity to the movableobjects. The system in this example includes an ultra-wideband (UWB)pulse transmitter coupled to a movable object in a physical environmentand configured to broadcast a pulse comprising a unique identifier, atleast two synchronized receivers at fixed receiver locations relative tothe physical environment. An object location application calculates acurrent object location of the movable object based on the broadcastpulse. An eyewear device in paired communication with the receiversincludes a processor, a memory, a localization application, a renderingapplication, and a display. The localization application determines acurrent eyewear location of the eyewear device. The renderingapplication presents a virtual element on a display as an overlayrelative to the calculated current object location and in relativeproximity to the determined current eyewear location.

The following detailed description includes systems, methods,techniques, instruction sequences, and computing machine programproducts illustrative of examples set forth in the disclosure. Numerousdetails and examples are included for the purpose of providing athorough understanding of the disclosed subject matter and its relevantteachings. Those skilled in the relevant art, however, may understandhow to apply the relevant teachings without such details. Aspects of thedisclosed subject matter are not limited to the specific devices,systems, and method described because the relevant teachings can beapplied or practice in a variety of ways. The terminology andnomenclature used herein is for the purpose of describing particularaspects only and is not intended to be limiting. In general, well-knowninstruction instances, protocols, structures, and techniques are notnecessarily shown in detail.

The terms “coupled” or “connected” as used herein refer to any logical,optical, physical, or electrical connection, including a link or thelike by which the electrical or magnetic signals produced or supplied byone system element are imparted to another coupled or connected systemelement. Unless described otherwise, coupled or connected elements ordevices are not necessarily directly connected to one another and may beseparated by intermediate components, elements, or communication media,one or more of which may modify, manipulate, or carry the electricalsignals. The term “on” means directly supported by an element orindirectly supported by the element through another element that isintegrated into or supported by the element.

The term “proximal” is used to describe an item or part of an item thatis situated near, adjacent, or next to an object or person; or that iscloser relative to other parts of the item, which may be described as“distal.” For example, the end of an item nearest an object may bereferred to as the proximal end, whereas the generally opposing end maybe referred to as the distal end.

The orientations of the eyewear device, other mobile devices, associatedcomponents and any other devices incorporating a camera, an inertialmeasurement unit, or both such as shown in any of the drawings, aregiven by way of example only, for illustration and discussion purposes.In operation, the eyewear device may be oriented in any other directionsuitable to the particular application of the eyewear device; forexample, up, down, sideways, or any other orientation. Also, to theextent used herein, any directional term, such as front, rear, inward,outward, toward, left, right, lateral, longitudinal, up, down, upper,lower, top, bottom, side, horizontal, vertical, and diagonal are used byway of example only, and are not limiting as to the direction ororientation of any camera or inertial measurement unit as constructed oras otherwise described herein.

Advanced AR technologies, such as computer vision and object tracking,may be used to produce a perceptually enriched and immersive experience.Computer vision algorithms extract three-dimensional data about thephysical world from the data captured in digital images or video. Objectrecognition and tracking algorithms are used to detect an object in adigital image or video, estimate its orientation or pose, and track itsmovement over time. Hand and finger recognition and tracking in realtime is one of the most challenging and processing-intensive tasks inthe field of computer vision.

The term “pose” refers to the static position and orientation of anobject at a particular instant in time. The term “gesture” refers to theactive movement of an object, such as a hand, through a series of poses,sometimes to convey a signal or idea. The terms, pose and gesture, aresometimes used interchangeably in the field of computer vision andaugmented reality. As used herein, the terms “pose” or “gesture” (orvariations thereof) are intended to be inclusive of both poses andgestures; in other words, the use of one term does not exclude theother.

Additional objects, advantages and novel features of the examples willbe set forth in part in the following description, and in part willbecome apparent to those skilled in the art upon examination of thefollowing and the accompanying drawings or may be learned by productionor operation of the examples. The objects and advantages of the presentsubject matter may be realized and attained by means of themethodologies, instrumentalities and combinations particularly pointedout in the appended claims.

Reference now is made in detail to the examples illustrated in theaccompanying drawings and discussed below.

FIG. 1A is a side view (right) of an example hardware configuration ofan eyewear device 100 which includes a touch-sensitive input device ortouchpad 181. As shown, the touchpad 181 may have a boundary that issubtle and not easily seen; alternatively, the boundary may be plainlyvisible or include a raised or otherwise tactile edge that providesfeedback to the user about the location and boundary of the touchpad181. In other implementations, the eyewear device 100 may include atouchpad on the left side.

The surface of the touchpad 181 is configured to detect finger touches,taps, and gestures (e.g., moving touches) for use with a GUI displayedby the eyewear device, on an image display, to allow the user tonavigate through and select menu options in an intuitive manner, whichenhances and simplifies the user experience.

Detection of finger inputs on the touchpad 181 can enable severalfunctions. For example, touching anywhere on the touchpad 181 may causethe GUI to display or highlight an item on the image display, which maybe projected onto at least one of the optical assemblies 180A, 180B.Double tapping on the touchpad 181 may select an item or icon. Slidingor swiping a finger in a particular direction (e.g., from front to back,back to front, up to down, or down to) may cause the items or icons toslide or scroll in a particular direction; for example, to move to anext item, icon, video, image, page, or slide. Sliding the finger inanother direction may slide or scroll in the opposite direction; forexample, to move to a previous item, icon, video, image, page, or slide.The touchpad 181 can be virtually anywhere on the eyewear device 100.

In one example, an identified finger gesture of a single tap on thetouchpad 181, initiates selection or pressing of a graphical userinterface element in the image presented on the image display of theoptical assembly 180A, 180B. An adjustment to the image presented on theimage display of the optical assembly 180A, 180B based on the identifiedfinger gesture can be a primary action which selects or submits thegraphical user interface element on the image display of the opticalassembly 180A, 180B for further display or execution.

As shown, the eyewear device 100 includes a right visible-light camera114B. As further described herein, two cameras 114A, 114B capture imageinformation for a scene from two separate viewpoints. The two capturedimages may be used to project a three-dimensional display onto an imagedisplay for viewing with 3D glasses.

The eyewear device 100 includes a right optical assembly 180B with animage display to present images, such as depth images. As shown in FIGS.1A and 1B, the eyewear device 100 includes the right visible-lightcamera 114B. The eyewear device 100 can include multiple visible-lightcameras 114A, 114B that form a passive type of three-dimensional camera,such as stereo camera, of which the right visible-light camera 114B islocated on a right corner 110B. As shown in FIGS. 1C-D, the eyeweardevice 100 also includes a left visible-light camera 114A.

Left and right visible-light cameras 114A, 114B are sensitive to thevisible-light range wavelength. Each of the visible-light cameras 114A,114B have a different frontward facing field of view which areoverlapping to enable generation of three-dimensional depth images, forexample, right visible-light camera 114B depicts a right field of view111B. Generally, a “field of view” is the part of the scene that isvisible through the camera at a particular position and orientation inspace. The fields of view 111A and 111B have an overlapping field ofview 304 (FIG. 3 ). Objects or object features outside the field of view111A, 111B when the visible-light camera captures the image are notrecorded in a raw image (e.g., photograph or picture). The field of viewdescribes an angle range or extent, which the image sensor of thevisible-light camera 114A, 114B picks up electromagnetic radiation of agiven scene in a captured image of the given scene. Field of view can beexpressed as the angular size of the view cone; i.e., an angle of view.The angle of view can be measured horizontally, vertically, ordiagonally.

In an example configuration, one or both visible-light cameras 114A,114B has a field of view of 100° and a resolution of 480×480 pixels. The“angle of coverage” describes the angle range that a lens ofvisible-light cameras 114A, 114B or infrared camera 410 (see FIG. 2A)can effectively image. Typically, the camera lens produces an imagecircle that is large enough to cover the film or sensor of the cameracompletely, possibly including some vignetting (e.g., a darkening of theimage toward the edges when compared to the center). If the angle ofcoverage of the camera lens does not fill the sensor, the image circlewill be visible, typically with strong vignetting toward the edge, andthe effective angle of view will be limited to the angle of coverage.

Examples of such visible-light cameras 114A, 114B include ahigh-resolution complementary metal-oxide-semiconductor (CMOS) imagesensor and a digital VGA camera (video graphics array) capable ofresolutions of 480p (e.g., 640×480 pixels), 720p, 1080p, or greater.Other examples include visible-light cameras 114A, 114B that can capturehigh-definition (HD) video at a high frame rate (e.g., thirty to sixtyframes per second, or more) and store the recording at a resolution of1216 by 1216 pixels (or greater).

The eyewear device 100 may capture image sensor data from thevisible-light cameras 114A, 114B along with geolocation data, digitizedby an image processor, for storage in a memory. The visible-lightcameras 114A, 114B capture respective left and right raw images in thetwo-dimensional space domain that comprise a matrix of pixels on atwo-dimensional coordinate system that includes an X-axis for horizontalposition and a Y-axis for vertical position. Each pixel includes a colorattribute value (e.g., a red pixel light value, a green pixel lightvalue, or a blue pixel light value); and a position attribute (e.g., anX-axis coordinate and a Y-axis coordinate).

In order to capture stereo images for later display as athree-dimensional projection, the image processor 412 (shown in FIG. 4 )may be coupled to the visible-light cameras 114A, 114B to receive andstore the visual image information. The image processor 412, or anotherprocessor, controls operation of the visible-light cameras 114A, 114B toact as a stereo camera simulating human binocular vision and may add atimestamp to each image. The timestamp on each pair of images allowsdisplay of the images together as part of a three-dimensionalprojection. Three-dimensional projections produce an immersive,life-like experience that is desirable in a variety of contexts,including virtual reality (VR) and video gaming.

FIG. 1B is a perspective, cross-sectional view of a right corner 110B ofthe eyewear device 100 of FIG. 1A depicting the right visible-lightcamera 114B of the camera system, and a circuit board. FIG. 1C is a sideview (left) of an example hardware configuration of an eyewear device100 of FIG. 1A, which shows a left visible-light camera 114A of thecamera system. FIG. 1D is a perspective, cross-sectional view of a leftcorner 110A of the eyewear device of FIG. 1C depicting the leftvisible-light camera 114A of the three-dimensional camera, and a circuitboard.

Construction and placement of the left visible-light camera 114A issubstantially similar to the right visible-light camera 114B, except theconnections and coupling are on the left lateral side 170A. As shown inthe example of FIG. 1B, the eyewear device 100 includes the rightvisible-light camera 114B and a circuit board 140B, which may be aflexible printed circuit board (PCB). A right hinge 126B connects theright corner 110B to a right temple 125B of the eyewear device 100. Insome examples, components of the right visible-light camera 114B, theflexible PCB 140B, or other electrical connectors or contacts may belocated on the right temple 125B or the right hinge 126B. A left hinge126B connects the left corner 110A to a left temple 125A of the eyeweardevice 100. In some examples, components of the left visible-lightcamera 114A, the flexible PCB 140A, or other electrical connectors orcontacts may be located on the left temple 125A or the left hinge 126A.

The right corner 110B includes corner body 190 and a corner cap, withthe corner cap omitted in the cross-section of FIG. 1B. Disposed insidethe right corner 110B are various interconnected circuit boards, such asPCBs or flexible PCBs, that include controller circuits for rightvisible-light camera 114B, microphone(s), low-power wireless circuitry(e.g., for wireless short range network communication via Bluetooth™),high-speed wireless circuitry (e.g., for wireless local area networkcommunication via Wi-Fi).

The right visible-light camera 114B is coupled to or disposed on theflexible PCB 140B and covered by a visible-light camera cover lens,which is aimed through opening(s) formed in the frame 105. For example,the right rim 107B of the frame 105, shown in FIG. 2A, is connected tothe right corner 110B and includes the opening(s) for the visible-lightcamera cover lens. The frame 105 includes a front side configured toface outward and away from the eye of the user. The opening for thevisible-light camera cover lens is formed on and through the front oroutward-facing side of the frame 105. In the example, the rightvisible-light camera 114B has an outward-facing field of view 111B(shown in FIG. 3 ) with a line of sight or perspective that iscorrelated with the right eye of the user of the eyewear device 100. Thevisible-light camera cover lens can also be adhered to a front side oroutward-facing surface of the right corner 110B in which an opening isformed with an outward-facing angle of coverage, but in a differentoutwardly direction. The coupling can also be indirect via interveningcomponents.

As shown in FIG. 1B, flexible PCB 140B is disposed inside the rightcorner 110B and is coupled to one or more other components housed in theright corner 110B. Although shown as being formed on the circuit boardsof the right corner 110B, the right visible-light camera 114B can beformed on the circuit boards of the left corner 110A, the temples 125A,125B, or the frame 105.

FIGS. 2A and 2B are perspective views, from the rear, of examplehardware configurations of the eyewear device 100, including twodifferent types of image displays. The eyewear device 100 is sized andshaped in a form configured for wearing by a user; the form ofeyeglasses is shown in the example. The eyewear device 100 can takeother forms and may incorporate other types of frameworks; for example,a headgear, a headset, or a helmet.

In the eyeglasses example, eyewear device 100 includes a frame 105including a left rim 107A connected to a right rim 107B via a bridge 106adapted to be supported by a nose of the user. The left and right rims107A, 107B include respective apertures 175A, 175B, which hold arespective optical element 180A, 180B, such as a lens and a displaydevice. As used herein, the term “lens” is meant to include transparentor translucent pieces of glass or plastic having curved or flat surfacesthat cause light to converge or diverge or that cause little or noconvergence or divergence.

Although shown as having two optical elements 180A, 180B, the eyeweardevice 100 can include other arrangements, such as a single opticalelement (or it may not include any optical element 180A, 180B),depending on the application or the intended user of the eyewear device100. As further shown, eyewear device 100 includes a left corner 110Aadjacent the left lateral side 170A of the frame 105 and a right corner110B adjacent the right lateral side 170B of the frame 105. The corners110A, 110B may be integrated into the frame 105 on the respective sides170A, 170B (as illustrated) or implemented as separate componentsattached to the frame 105 on the respective sides 170A, 170B.Alternatively, the corners 110A, 110B may be integrated into temples(not shown) attached to the frame 105.

In one example, the image display of optical assembly 180A, 180Bincludes an integrated image display. As shown in FIG. 2A, each opticalassembly 180A, 180B includes a suitable display matrix 177, such as aliquid crystal display (LCD), an organic light-emitting diode (OLED)display, or any other such display. Each optical assembly 180A, 180Balso includes an optical layer or layers 176, which can include lenses,optical coatings, prisms, mirrors, waveguides, optical strips, and otheroptical components in any combination. The optical layers 176A, 176B, .. . 176N (shown as 176A-N in FIG. 2A and herein) can include a prismhaving a suitable size and configuration and including a first surfacefor receiving light from a display matrix and a second surface foremitting light to the eye of the user. The prism of the optical layers176A-N extends over all or at least a portion of the respectiveapertures 175A, 175B formed in the left and right rims 107A, 107B topermit the user to see the second surface of the prism when the eye ofthe user is viewing through the corresponding left and right rims 107A,107B. The first surface of the prism of the optical layers 176A-N facesupwardly from the frame 105 and the display matrix 177 overlies theprism so that photons and light emitted by the display matrix 177impinge the first surface. The prism is sized and shaped so that thelight is refracted within the prism and is directed toward the eye ofthe user by the second surface of the prism of the optical layers176A-N. In this regard, the second surface of the prism of the opticallayers 176A-N can be convex to direct the light toward the center of theeye. The prism can optionally be sized and shaped to magnify the imageprojected by the display matrix 177, and the light travels through theprism so that the image viewed from the second surface is larger in oneor more dimensions than the image emitted from the display matrix 177.

In one example, the optical layers 176A-N may include an LCD layer thatis transparent (keeping the lens open) unless and until a voltage isapplied which makes the layer opaque (closing or blocking the lens). Theimage processor 412 on the eyewear device 100 may execute programming toapply the voltage to the LCD layer in order to produce an active shuttersystem, making the eyewear device 100 suitable for viewing visualcontent when displayed as a three-dimensional projection. Technologiesother than LCD may be used for the active shutter mode, including othertypes of reactive layers that are responsive to a voltage or anothertype of input.

In another example, the image display device of optical assembly 180A,180B includes a projection image display as shown in FIG. 2B. Eachoptical assembly 180A, 180B includes a laser projector 150, which is athree-color laser projector using a scanning mirror or galvanometer.During operation, an optical source such as a laser projector 150 isdisposed in or on one of the temples 125A, 125B of the eyewear device100. Optical assembly 180B in this example includes one or more opticalstrips 155A, 155B, . . . 155N (shown as 155A-N in FIG. 2B) which arespaced apart and across the width of the lens of each optical assembly180A, 180B or across a depth of the lens between the front surface andthe rear surface of the lens.

As the photons projected by the laser projector 150 travel across thelens of each optical assembly 180A, 180B, the photons encounter theoptical strips 155A-N. When a particular photon encounters a particularoptical strip, the photon is either redirected toward the user's eye, orit passes to the next optical strip. A combination of modulation oflaser projector 150, and modulation of optical strips, may controlspecific photons or beams of light. In an example, a processor controlsoptical strips 155A-N by initiating mechanical, acoustic, orelectromagnetic signals. Although shown as having two optical assemblies180A, 180B, the eyewear device 100 can include other arrangements, suchas a single or three optical assemblies, or each optical assembly 180A,180B may have arranged different arrangement depending on theapplication or intended user of the eyewear device 100.

As further shown in FIGS. 2A and 2B, eyewear device 100 includes a leftcorner 110A adjacent the left lateral side 170A of the frame 105 and aright corner 110B adjacent the right lateral side 170B of the frame 105.The corners 110A, 110B may be integrated into the frame 105 on therespective lateral sides 170A, 170B (as illustrated) or implemented asseparate components attached to the frame 105 on the respective sides170A, 170B. Alternatively, the corners 110A, 110B may be integrated intotemples 125A, 125B attached to the frame 105.

In another example, the eyewear device 100 shown in FIG. 2B may includetwo projectors, a left projector 150A (not shown) and a right projector150B (shown as projector 150). The left optical assembly 180A mayinclude a left display matrix 177A (not shown) or a left set of opticalstrips 155′A, 155′B, . . . 155′N (155 prime, A through N, not shown)which are configured to interact with light from the left projector150A. Similarly, the right optical assembly 180B may include a rightdisplay matrix 177B (not shown) or a right set of optical strips 155″A,155″B, . . . 155″N (155 double prime, A through N, not shown) which areconfigured to interact with light from the right projector 150B. In thisexample, the eyewear device 100 includes a left display and a rightdisplay.

FIG. 3 is a diagrammatic depiction of a three-dimensional scene 306, aleft raw image 302A captured by a left visible-light camera 114A, and aright raw image 302B captured by a right visible-light camera 114B. Theleft field of view 111A may overlap, as shown, with the right field ofview 111B. The overlapping field of view 304 represents that portion ofthe image captured by both cameras 114A, 114B. The term ‘overlapping’when referring to field of view means the matrix of pixels in thegenerated raw images overlap by thirty percent (30%) or more.‘Substantially overlapping’ means the matrix of pixels in the generatedraw images—or in the infrared image of scene—overlap by fifty percent(50%) or more. As described herein, the two raw images 302A, 302B may beprocessed to include a timestamp, which allows the images to bedisplayed together as part of a three-dimensional projection.

For the capture of stereo images, as illustrated in FIG. 3 , a pair ofraw red, green, and blue (RGB) images are captured of a real scene 306at a given moment in time—a left raw image 302A captured by the leftcamera 114A and right raw image 302B captured by the right camera 114B.When the pair of raw images 302A, 302B are processed (e.g., by the imageprocessor 412), depth images are generated. The generated depth imagesmay be viewed on an optical assembly 180A, 180B of an eyewear device, onanother display (e.g., the image display 580 on a mobile device 401), oron a screen.

The generated depth images are in the three-dimensional space domain andcan comprise a matrix of vertices on a three-dimensional locationcoordinate system that includes an X axis for horizontal position (e.g.,length), a Y axis for vertical position (e.g., height), and a Z axis fordepth (e.g., distance). Each vertex may include a color attribute (e.g.,a red pixel light value, a green pixel light value, or a blue pixellight value); a position attribute (e.g., an X location coordinate, a Ylocation coordinate, and a Z location coordinate); a texture attribute;a reflectance attribute; or a combination thereof. The texture attributequantifies the perceived texture of the depth image, such as the spatialarrangement of color or intensities in a region of vertices of the depthimage.

In one example, the tracking and display system 400 (FIG. 4 ) includesthe eyewear device 100, which includes a frame 105 and a left temple125A extending from a left lateral side 170A of the frame 105 and aright temple 125B extending from a right lateral side 170B of the frame105. The eyewear device 100 may further include at least twovisible-light cameras 114A, 114B having overlapping fields of view. Inone example, the eyewear device 100 includes a left visible-light camera114A with a left field of view 111A, as illustrated in FIG. 3 . The leftcamera 114A is connected to the frame 105 or the left temple 125A tocapture a left raw image 302A from the left side of scene 306. Theeyewear device 100 further includes a right visible-light camera 114Bwith a right field of view 111B. The right camera 114B is connected tothe frame 105 or the right temple 125B to capture a right raw image 302Bfrom the right side of scene 306.

FIG. 4 is a functional block diagram of an example tracking and displaysystem 400 that includes a wearable device (e.g., an eyewear device100), a mobile device 401, and a server system 498 connected via variousnetworks 495 such as the Internet. As shown, the tracking and displaysystem 400 includes a low-power wireless connection 425 and a high-speedwireless connection 437 between the eyewear device 100 and the mobiledevice 401, as well as a wireless connection between the eyewear device10 and one or more ultra-wideband (UWB) receivers 680.

As shown in FIG. 4 , the eyewear device 100 includes one or morevisible-light cameras 114A, 114B that capture still images, videoimages, or both still and video images, as described herein. The cameras114A, 114B may have a direct memory access (DMA) to high-speed circuitry430 and function as a stereo camera. The cameras 114A, 114B may be usedto capture initial-depth images that may be rendered intothree-dimensional (3D) models that are texture-mapped images of a red,green, and blue (RGB) imaged scene. The device 100 may also include adepth sensor 213, which uses infrared signals to estimate the positionof objects relative to the device 100. The depth sensor 213 in someexamples includes one or more infrared emitter(s) 215 and infraredcamera(s) 410.

The eyewear device 100 further includes two image displays of eachoptical assembly 180A, 180B (one associated with the left side 170A andone associated with the right side 170B). The eyewear device 100 alsoincludes an image display driver 442, an image processor 412, low-powercircuitry 420, and high-speed circuitry 430. The image displays of eachoptical assembly 180A, 180B are for presenting images, including stillimages, video images, or still and video images. The image displaydriver 442 is coupled to the image displays of each optical assembly180A, 180B in order to control the display of images.

The eyewear device 100 additionally includes one or more speakers 440(e.g., one associated with the left side of the eyewear device andanother associated with the right side of the eyewear device). Thespeakers 440 may be incorporated into the frame 105, temples 125, orcorners 110 of the eyewear device 100. The one or more speakers 440 aredriven by audio processor 443 under control of low-power circuitry 420,high-speed circuitry 430, or both. The speakers 440 are for presentingaudio signals including, for example, a beat track. The audio processor443 is coupled to the speakers 440 in order to control the presentationof sound.

The components shown in FIG. 4 for the eyewear device 100 are located onone or more circuit boards, for example a printed circuit board (PCB) orflexible printed circuit (FPC), located in the rims or temples.Alternatively, or additionally, the depicted components can be locatedin the corners, frames, hinges, or bridge of the eyewear device 100.Left and right visible-light cameras 114A, 114B can include digitalcamera elements such as a complementary metal-oxide-semiconductor (CMOS)image sensor, a charge-coupled device, a lens, or any other respectivevisible or light capturing elements that may be used to capture data,including still images or video of scenes with unknown objects.

As shown in FIG. 4 , high-speed circuitry 430 includes a high-speedprocessor 432, a memory 434, and high-speed wireless circuitry 436. Inthe example, the image display driver 442 is coupled to the high-speedcircuitry 430 and operated by the high-speed processor 432 in order todrive the left and right image displays of each optical assembly 180A,180B. High-speed processor 432 may be any processor capable of managinghigh-speed communications and operation of any general computing systemneeded for eyewear device 100. High-speed processor 432 includesprocessing resources needed for managing high-speed data transfers onhigh-speed wireless connection 437 to a wireless local area network(WLAN) using high-speed wireless circuitry 436.

In some examples, the high-speed processor 432 executes an operatingsystem such as a LINUX operating system or other such operating systemof the eyewear device 100 and the operating system is stored in memory434 for execution. In addition to any other responsibilities, thehigh-speed processor 432 executes a software architecture for theeyewear device 100 that is used to manage data transfers with high-speedwireless circuitry 436. In some examples, high-speed wireless circuitry436 is configured to implement Institute of Electrical and ElectronicEngineers (IEEE) 802.11 communication standards, also referred to hereinas Wi-Fi. In other examples, other high-speed communications standardsmay be implemented by high-speed wireless circuitry 436.

The low-power circuitry 420 includes a low-power processor 422 andlow-power wireless circuitry 424. The low-power wireless circuitry 424and the high-speed wireless circuitry 436 of the eyewear device 100 caninclude short-range transceivers (Bluetooth™ or Bluetooth Low-Energy(BLE)) and wireless wide, local, or wide-area network transceivers(e.g., cellular or Wi-Fi). Mobile device 401, including the transceiverscommunicating via the low-power wireless connection 425 and thehigh-speed wireless connection 437, may be implemented using details ofthe architecture of the eyewear device 100, as can other elements of thenetwork 495.

Memory 434 includes any storage device capable of storing various dataand applications, including, among other things, camera data generatedby the left and right visible-light cameras 114A, 114B, the infraredcamera(s) 410, the image processor 412, and images generated for displayby the image display driver 442 on the image display of each opticalassembly 180A, 180B. Although the memory 434 is shown as integrated withhigh-speed circuitry 430, the memory 434 in other examples may be anindependent, standalone element of the eyewear device 100. In certainsuch examples, electrical routing lines may provide a connection througha chip that includes the high-speed processor 432 from the imageprocessor 412 or low-power processor 422 to the memory 434. In otherexamples, the high-speed processor 432 may manage addressing of memory434 such that the low-power processor 422 will boot the high-speedprocessor 432 any time that a read or write operation involving memory434 is needed.

As shown in FIG. 4 , the high-speed processor 432 of the eyewear device100 can be coupled to the camera system (visible-light cameras 114A,114B), the image display driver 442, the user input device 491, and thememory 434. As shown in FIG. 5 , the CPU 530 of the mobile device 401may be coupled to a camera system 570, a mobile display driver 582, auser input layer 591, and a memory 540A.

The server system 498 may be one or more computing devices as part of aservice or network computing system, for example, that include aprocessor, a memory, and network communication interface to communicateover the network 495 with an eyewear device 100 and a mobile device 401.

The output components of the eyewear device 100 include visual elements,such as the left and right image displays associated with each lens oroptical assembly 180A, 180B as described in FIGS. 2A and 2B (e.g., adisplay such as a liquid crystal display (LCD), a plasma display panel(PDP), a light emitting diode (LED) display, a projector, or awaveguide). The eyewear device 100 may include a user-facing indicator(e.g., an LED, a loudspeaker, or a vibrating actuator), or anoutward-facing signal (e.g., an LED, a loudspeaker). The image displaysof each optical assembly 180A, 180B are driven by the image displaydriver 442. In some example configurations, the output components of theeyewear device 100 further include additional indicators such as audibleelements (e.g., loudspeakers), tactile components (e.g., an actuatorsuch as a vibratory motor to generate haptic feedback), and other signalgenerators. For example, the device 100 may include a user-facing set ofindicators, and an outward-facing set of signals. The user-facing set ofindicators are configured to be seen or otherwise sensed by the user ofthe device 100. For example, the device 100 may include an LED displaypositioned so the user can see it, a one or more speakers positioned togenerate a sound the user can hear, or an actuator to provide hapticfeedback the user can feel. The outward-facing set of signals areconfigured to be seen or otherwise sensed by an observer near the device100. Similarly, the device 100 may include an LED, a loudspeaker, or anactuator that is configured and positioned to be sensed by an observer.

The input components of the eyewear device 100 may include alphanumericinput components (e.g., a touch screen or touchpad configured to receivealphanumeric input, a photo-optical keyboard, or otheralphanumeric-configured elements), pointer-based input components (e.g.,a mouse, a touchpad, a trackball, a joystick, a motion sensor, or otherpointing instruments), tactile input components (e.g., a button switch,a touch screen or touchpad that senses the location, force or locationand force of touches or touch gestures, or other tactile-configuredelements), and audio input components (e.g., a microphone), and thelike. The mobile device 401 and the server system 498 may includealphanumeric, pointer-based, tactile, audio, and other input components.

In some examples, the eyewear device 100 includes a collection ofmotion-sensing components referred to as an inertial measurement unit472. The motion-sensing components may be micro-electro-mechanicalsystems (MEMS) with microscopic moving parts, often small enough to bepart of a microchip. The inertial measurement unit (IMU) 472 in someexample configurations includes an accelerometer, a gyroscope, and amagnetometer. The accelerometer senses the linear acceleration of thedevice 100 (including the acceleration due to gravity) relative to threeorthogonal axes (x, y, z). The gyroscope senses the angular velocity ofthe device 100 about three axes of rotation (pitch, roll, yaw).Together, the accelerometer and gyroscope can provide position,orientation, and motion data about the device relative to six axes (x,y, z, pitch, roll, yaw). The magnetometer, if present, senses theheading of the device 100 relative to magnetic north. The position ofthe device 100 may be determined by location sensors, such as a GPS unit473, one or more transceivers to generate relative position coordinates,altitude sensors or barometers, and other orientation sensors. Suchpositioning system coordinates can also be received over the wirelessconnections 425, 437 from the mobile device 401 via the low-powerwireless circuitry 424 or the high-speed wireless circuitry 436.

The IMU 472 may include or cooperate with a digital motion processor orprogramming that gathers the raw data from the components and compute anumber of useful values about the position, orientation, and motion ofthe device 100. For example, the acceleration data gathered from theaccelerometer can be integrated to obtain the velocity relative to eachaxis (x, y, z); and integrated again to obtain the position of thedevice 100 (in linear coordinates, x, y, and z). The angular velocitydata from the gyroscope can be integrated to obtain the position of thedevice 100 (in spherical coordinates). The programming for computingthese useful values may be stored in memory 434 and executed by thehigh-speed processor 432 of the eyewear device 100.

The eyewear device 100 may optionally include additional peripheralsensors, such as biometric sensors, specialty sensors, or displayelements integrated with eyewear device 100. For example, peripheraldevice elements may include any I/O components including outputcomponents, motion components, position components, or any other suchelements described herein. For example, the biometric sensors mayinclude components to detect expressions (e.g., hand expressions, facialexpressions, vocal expressions, body gestures, or eye tracking), tomeasure bio signals (e.g., blood pressure, heart rate, body temperature,perspiration, or brain waves), or to identify a person (e.g.,identification based on voice, retina, facial characteristics,fingerprints, or electrical bio signals such as electroencephalogramdata), and the like.

The mobile device 401 may be a smartphone, tablet, laptop computer,access point, or any other such device capable of connecting witheyewear device 100 using a low-power wireless connection 425 or ahigh-speed wireless connection 437. The mobile device 401 is connectedto the server system 498 and the network 495. The network 495 mayinclude any combination of wired and wireless connections.

The example tracking and display system 400, as shown in FIG. 4 ,includes a plurality of ultra-wideband (UWB) pulse transmitters 620 inwireless communication with one or more UWB receivers 680. The UWBreceivers 680 are in wireless communication with one or more eyeweardevices 100 which, in turn, are in wireless communication with one ormore mobile devices 401. In some implementations, these devices 620,680, 100, 401 operate as nodes in a network. Network data may be storedlocally or remotely, on the servers or securely in the cloud. UWBtransmitters 620 are paired with the UWB receivers 680. The eyeweardevices 100 and mobile devices 410 operate as subscribers to the UWBsystem 620, 680.

One or more of the UWB receivers 680 in some example implementations arecoupled to a virtual element library 480, a transmitter database 485,and a movable object database 490. The eyewear devices 100, as shown,may also be coupled to one or more of the database elements 480, 485,490.

The virtual element library 480 stores data about each of a plurality ofvirtual elements 700, including a name, a serial number or otheridentifier, and a set of image assets for use in rendering the virtualelement 700 for display in a variety of contexts. The virtual elementlibrary 480 may also include, for each virtual element 700, a desiredsize (e.g., six inches tall) relative to the physical environment, anddata about the one or more movable objects 610 where the virtual element700 will be displayed.

The transmitter database 485 stores data about each of the UWB pulsetransmitters 620, including a unique transmitter identifier, a status,and a network number or other pairing information about the UWBreceivers 680 to which each transmitter 620 is paired.

The movable object database 490 stores data about each of a plurality ofmovable objects 610, including an object name, an object identifier orstock keeping unit (SKU), and a copy of (or a relational link to) theunique transmitter identifier for each of the one or more UWB pulsetransmitters 620 that are coupled to each movable object 610. Forexample, a movable object 610 such as a round tabletop may be associatedwith an object name (e.g., round tabletop), an object identifier or SKU(e.g., Tab-Round-4-09), and a copy of the unique transmitter identifierattached to the table (e.g., Tx-CTR-09). In practice, when a transmitter620 is attached to a movable object 610, data about the movable object610 is added to the movable object database 490. The movable objectdatabase 490 in some implementations also stores a predefined objectmesh 611 which includes one or more known dimensions associated witheach movable object 610. For example, the predefined object mesh 611 fora movable object 610, such as the round tabletop 610-1 shown in FIG. 7 ,may include a diameter and a thickness. If the movable object 610includes the entire table, the object mesh 611 includes geometric dataand dimensions associated with all parts of the table, including thetop, pedestal, and legs. The object mesh 611 for other objects, such asfolding chairs, collapsible tables, and machinery, may be geometricallycomplex. The predefined object mesh 611 for a door 610-2, shown in FIG.7 , may include a width, height, and thickness, as well as geometricdata about the doorknob, hinges, panels, molding, rails, mullions, andother features of the door. The predefined object mesh 611 for a servingtray 610-3, shown in FIG. 7 , may include a diameter and a thickness, aswell as geometric data about the perimeter edge and other surfacefeatures.

The libraries and databases, in some implementations, operate as a setof relational databases with one or more shared keys linking the data toother database entries, and a database management system for maintainingand querying each database.

The example tracking and display system 400, as shown in FIG. 4 ,includes an object location application 910, a localization application915, and a rendering application 920. The eyewear devices 100, as shown,may be coupled to one or more of the applications 910, 915, 920.

The object location application 910 includes the multilaterationalgorithms that compute the precise location of each pulse transmitter620 in the network. Based on the location of each transmitter 620, theobject location application 910 calculates a current location 615 forthe movable object 610 associated with that particular transmitter 620(e.g., by retrieving data stored in the databases 480, 485, 490). Insome example implementations, object location application 910 isexecuted by or on one or more of the UWB receivers 680, as shown in FIG.5

The localization application 915 determines a current location 902 ofthe eyewear device 100 relative to the physical environment. Thelocalization data may be derived from the data in one or more imagescaptured by a camera, an IMU unit 472, a GPS unit 473, or a combinationthereof.

In some example implementations, the localization application 915utilizes the fixed locations 685 of the one or more UWB receivers 680 toupdate the current eyewear position 902 relative to the physicalenvironment 600. The processor 432 of the eyewear device 100 determinesits position with respect to one or more receiver locations 685 relativeto the coordinate system (x, y, z) for the physical environment 600,thereby determining the current eyewear position 902 within thecoordinate system. Additionally, the processor 432 may determine a headpose (roll, pitch, and yaw) of the eyewear device 100 within theenvironment by using two or more receiver locations 685 or by using oneor more other known location. In this example, the known receiverlocations 685 operate similar to the registered locations of virtualmarkers in augmented reality.

In other example implementations, the processor 432 within the eyeweardevice 100 may construct a map of the physical environment 600surrounding the eyewear device 100, determine a current location 902 ofthe eyewear device within the mapped environment, and determine arelative position of the eyewear device to one or more objects in themapped environment. In some implementations, the processor 432 mayconstruct the map and execute the localization application 915 todetermine the current eyewear location 902 relative to the physicalenvironment 600. The localization application 915 may utilize asimultaneous localization and mapping (SLAM) algorithm using datareceived from one or more sensors. Sensor data includes images receivedfrom one or both of the cameras 114A, 114B, distance(s) received from alaser range finder, position information received from a GPS unit 473,motion and acceleration data received from an IMU 572, or a combinationof data from such sensors, or from other sensors that provide datauseful in determining positional information. In the context ofaugmented reality, a SLAM algorithm is used to construct and update amap of an environment, while simultaneously tracking and updating thelocation of a device (or a user) within the mapped environment. Themathematical solution can be approximated using various statisticalmethods, such as particle filters, Kalman filters, extended Kalmanfilters, and covariance intersection. In a system that includes ahigh-definition (HD) video camera that captures video at a high framerate (e.g., thirty frames per second), the SLAM algorithm updates themap and the location of objects at least as frequently as the framerate; in other words, calculating and updating the mapping andlocalization thirty times per second.

The rendering application 920 prepares a virtual element 700 forpresentation on a display as an overlay relative to a movable object610. In this context, the term “overlay” means and includes presenting avirtual element 700 on a display in the foreground, relative to aphysical, movable object 610 which appears in the background, except insituations where part of the virtual element 700 is obscured by aportion of the movable object 610 (e.g., when a movable door partiallyobscures part of a virtual element 700 presented nearby). The renderingapplication 920 may utilize data from the object location application910, including the current movable object location 615, and from thelocalization application 915, including the current eyewear location902. With this data, the rendering application 920 presents the virtualelement 700 for display near the current movable object location 615 andin relative proximity to the current eyewear location 902. As usedherein, the term “relative proximity” means and includes thecoordination in a physical space between and among the current eyewearlocation 902, the current movable object location 615 (in conjunctionwith the location of each attached pulse transmitter 620), the virtualelement location 715, and the UWB receiver locations 685, all of whichare expressed in coordinates (x, y, z) relative to the physicalenvironment 600 (and relative to the eyewear location 902, in someimplementations) as illustrated in FIG. 8 . For example, presenting avirtual element 700 on the display 180B of an eyewear device 100requires localizing the eyewear device 100 in the physical environmentand calculating the movable object location 615, so the renderingapplication 920 can then present the virtual element 700 on the displayso that it appears to be near the movable object 610. As both theeyewear device 100 and the movable object 610 are moving through theenvironment, the rendering application 920 continually updates thedisplay so that the virtual element 700 persistently appears near themovable object 610. For example, as shown in FIG. 8 , for a virtualelement 700 (e.g., a seated figure) associated with a movable object 610(e.g., a handheld serving tray), the rendering application 920continually updates the display so the seated figure appears to remainon the serving tray as the serving tray moves, and with regard to anymovement of the eyewear device 100 which supports the display 180B.

In a related aspect, the tracking and display system 400 accomplishesthe real-time tracking of movable objects, and the display of virtualelements, without using computer vision and a tracking application(e.g., simultaneous localization and mapping (SLAM)). The physicalenvironment 600, including the fixed features and stationary objects, isstored as a predefined static mesh 605, as described herein, instead ofusing a tracking application to map the fixed environment repeatedly.Nonetheless, in some implementations, the tracking and display system400 cooperates with a tracking application that is configured to trackmoving items, such as people and objects which are not attached to apulse transmitter.

The tracking and display system 400, as shown in FIG. 4 , includescomputing devices, including the eyewear device 100, mobile device, andreceivers 680, in a network. The applications 910, 915, 920 utilize amemory for storing instructions and a processor for executing theinstructions. Execution of the instructions configure the devices tocommunicate, exchange data, and otherwise cooperate in the network. Theapplications may utilize the memory 434 of the eyewear device 100, thememory elements 540A, 540B, 540C of the mobile device 401, and anymemory elements associated with the server 490 and the UWB receivers 680or transmitters 620. Moreover, the applications may utilize theprocessor elements 432, 422 of the eyewear device 100, the centralprocessing unit (CPU) 530 of the mobile device 401, and any processingelements associated with the server 490 and the UWB receivers 680 ortransmitters 620. In this this aspect, the memory and processingfunctions of the tracking and display system 400 can be shared ordistributed across the processors and memories of the eyewear device100, the mobile device 401, the server system 498, and the UWB receivers680 and transmitters 620.

FIG. 5 is a high-level functional block diagram of an example mobiledevice 401. Mobile device 401 includes a flash memory 540A which storesprogramming to be executed by the CPU 530 to perform all or a subset ofthe functions described herein.

The mobile device 401 may include a camera 570 that comprises at leasttwo visible-light cameras (first and second visible-light cameras withoverlapping fields of view) or at least one visible-light camera and adepth sensor with substantially overlapping fields of view. Flash memory540A may further include multiple images or video, which are generatedvia the camera 570.

As shown, the mobile device 401 includes an image display 580, a mobiledisplay driver 582 to control the image display 580, and a displaycontroller 584. In the example of FIG. 5 , the image display 580includes a user input layer 591 (e.g., a touchscreen) that is layered ontop of or otherwise integrated into the screen used by the image display580.

Examples of touchscreen-type mobile devices that may be used include(but are not limited to) a smart phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or other portable device.However, the structure and operation of the touchscreen-type devices isprovided by way of example; the subject technology as described hereinis not intended to be limited thereto. For purposes of this discussion,FIG. 5 therefore provides a block diagram illustration of the examplemobile device 401 with a user interface that includes a touchscreeninput layer 891 for receiving input (by touch, multi-touch, or gesture,and the like, by hand, stylus, or other tool) and an image display 580for displaying content.

As shown in FIG. 5 , the mobile device 401 includes at least one digitaltransceiver (XCVR) 510, shown as WWAN XCVRs, for digital wirelesscommunications via a wide-area wireless mobile communication network.The mobile device 401 also includes additional digital or analogtransceivers, such as short-range transceivers (XCVRs) 520 forshort-range network communication, such as via NFC, VLC, DECT, ZigBee,Bluetooth™, or Wi-Fi. For example, short range XCVRs 520 may take theform of any available two-way wireless local area network (WLAN)transceiver of a type that is compatible with one or more standardprotocols of communication implemented in wireless local area networks,such as one of the Wi-Fi standards under IEEE 802.11.

To generate location coordinates for positioning of the mobile device401, the mobile device 401 can include a global positioning system (GPS)receiver. Alternatively, or additionally the mobile device 401 canutilize either or both the short range XCVRs 520 and WWAN XCVRs 510 forgenerating location coordinates for positioning. For example, cellularnetwork, Wi-Fi, or Bluetooth™ based positioning systems can generatevery accurate location coordinates, particularly when used incombination. Such location coordinates can be transmitted to the eyeweardevice over one or more network connections via XCVRs 510, 520.

The client device 401 in some examples includes a collection ofmotion-sensing components referred to as an inertial measurement unit(IMU) 572 for sensing the position, orientation, and motion of theclient device 401. The motion-sensing components may bemicro-electro-mechanical systems (MEMS) with microscopic moving parts,often small enough to be part of a microchip. The inertial measurementunit (IMU) 572 in some example configurations includes an accelerometer,a gyroscope, and a magnetometer. The accelerometer senses the linearacceleration of the client device 401 (including the acceleration due togravity) relative to three orthogonal axes (x, y, z). The gyroscopesenses the angular velocity of the client device 401 about three axes ofrotation (pitch, roll, yaw). Together, the accelerometer and gyroscopecan provide position, orientation, and motion data about the devicerelative to six axes (x, y, z, pitch, roll, yaw). The magnetometer, ifpresent, senses the heading of the client device 401 relative tomagnetic north.

The IMU 572 may include or cooperate with a digital motion processor orprogramming that gathers the raw data from the components and compute anumber of useful values about the position, orientation, and motion ofthe client device 401. For example, the acceleration data gathered fromthe accelerometer can be integrated to obtain the velocity relative toeach axis (x, y, z); and integrated again to obtain the position of theclient device 401 (in linear coordinates, x, y, and z). The angularvelocity data from the gyroscope can be integrated to obtain theposition of the client device 401 (in spherical coordinates). Theprogramming for computing these useful values may be stored in on ormore memory elements 540A, 540B, 540C and executed by the CPU 530 of theclient device 401.

The transceivers 510, 520 (i.e., the network communication interface)conforms to one or more of the various digital wireless communicationstandards utilized by modern mobile networks. Examples of WWANtransceivers 510 include (but are not limited to) transceiversconfigured to operate in accordance with Code Division Multiple Access(CDMA) and 3rd Generation Partnership Project (3GPP) networktechnologies including, for example and without limitation, 3GPP type 2(or 3GPP2) and LTE, at times referred to as “4G.” For example, thetransceivers 510, 520 provide two-way wireless communication ofinformation including digitized audio signals, still image and videosignals, web page information for display as well as web-related inputs,and various types of mobile message communications to/from the mobiledevice 401.

The mobile device 401 further includes a microprocessor that functionsas a central processing unit (CPU); shown as CPU 530 in FIG. 4 . Aprocessor is a circuit having elements structured and arranged toperform one or more processing functions, typically various dataprocessing functions. Although discrete logic components could be used,the examples utilize components forming a programmable CPU. Amicroprocessor for example includes one or more integrated circuit (IC)chips incorporating the electronic elements to perform the functions ofthe CPU. The CPU 530, for example, may be based on any known oravailable microprocessor architecture, such as a Reduced Instruction SetComputing (RISC) using an ARM architecture, as commonly used today inmobile devices and other portable electronic devices. Of course, otherarrangements of processor circuitry may be used to form the CPU 530 orprocessor hardware in smartphone, laptop computer, and tablet.

The CPU 530 serves as a programmable host controller for the mobiledevice 401 by configuring the mobile device 401 to perform variousoperations, for example, in accordance with instructions or programmingexecutable by CPU 530. For example, such operations may include variousgeneral operations of the mobile device, as well as operations relatedto the programming for applications on the mobile device. Although aprocessor may be configured by use of hardwired logic, typicalprocessors in mobile devices are general processing circuits configuredby execution of programming.

The mobile device 401 includes a memory or storage system, for storingprogramming and data. In the example, the memory system may include aflash memory 540A, a random-access memory (RAM) 540B, and other memorycomponents 540C, as needed. The RAM 540B serves as short-term storagefor instructions and data being handled by the CPU 530, e.g., as aworking data processing memory. The flash memory 540A typically provideslonger-term storage.

Hence, in the example of mobile device 401, the flash memory 540A isused to store programming or instructions for execution by the CPU 530.Depending on the type of device, the mobile device 401 stores and runs amobile operating system through which specific applications areexecuted. Examples of mobile operating systems include Google Android,Apple iOS (for iPhone or iPad devices), Windows Mobile, Amazon Fire OS,RIM BlackBerry OS, or the like.

FIG. 6 is a functional block diagram of an example tracking and displaysystem 400 including ultra-wideband (UWB) pulse transmitters 620 coupledto movable objects 610, two UWB receivers 680, one or more eyeweardevices 100, one or more mobile devices 410, and a collection ofdatabase elements 480, 485, 490 as described herein. Each UWB pulsetransmitter 620 includes an antenna, as shown, for wirelesscommunication with the UWB receivers 680.

Each broadcast pulse includes a unique transmitter identifier which isused by the UWB receivers 680 to identify the transmitter that broadcasteach pulse. The pulse includes a data packet comprising a preamble and apayload, which contains bits of data. The physical layer of each pulseis assembled according to the standards set forth in IEEE 802.15.4a and4z. The pulse a short burst of electromagnetic energy having a durationsufficient to extract the bits of data, including data for measuring ordetermining the position of the transmitter.

In this example, a first pulse transmitter 620-1 is attached or coupledto a first movable object 610-1. Attached to the second movable object610-2 is a pair of second pulse transmitters 620-2 a, 620-2 b, and acompass 640. Attached to the third movable object 610-3 is a pair ofthird pulse transmitters 620-3 a, 620-3 b, and an accelerometer 650.

The UWB receivers 680 are placed in a physical environment 600 at fixedreceiver locations 685, as shown in FIG. 8 . The UWB receivers 680 aretime synchronized because the multilateration algorithms use thedifference between the times of arrival for each pulse at each receiver680 to calculate the precise location of each transmitter 620. Theprecise location of each transmitter 620 is then used to calculate acurrent object location 615 associated with each movable object 610. Inthe example shown in FIG. 6 , the first UWB receiver 680-1 includes anobject location application 910 for calculating the current objectlocation 615.

The UWB receivers 680 are in paired wireless communication with one ormore eyewear devices 100 and with one or more mobile devices 401, asshown. The transmitters 620, receivers 680, eyewear devices 100, andmobile devices 401 operate as nodes in a network. The transmitters 620are paired with the receivers 680. The eyewear devices 100 and mobiledevices 410 operate as subscribers to the UWB system 620, 680.

The eyewear device 100 as described herein includes a processor, amemory, a localization application 915, a rendering application 920, anda display 180B (as shown in FIG. 8 ). In use, the localizationapplication 915 determines a current eyewear location 902 for eacheyewear device 100. The rendering application 920 presents a virtualelement 700 on the display 180B at a virtual element location 715 as anoverlay relative to the calculated current object location 615 and inrelative proximity to the determined current eyewear location. Forexample, as illustrated in FIG. 8 , the process of rendering andpresenting a virtual element 700 on the display 180B of an eyeweardevice 100 requires localizing the eyewear device 100 with the physicalenvironment 600 and calculating the movable object location 615, so therendering application 920 can then present the virtual element 700 onthe display so that it appears to be near the movable object 610.

The virtual element 700 may be presented near the center of the movableobject 610 or at some other specified location or defined anchor pointon the movable object 610. Although the examples virtual elements shownherein are figures, the virtual element 700 may include any of a varietyof elements suitable for rendering on a display, including figurative orrealistic items, static or moving, alone or in combination with otheritems. The virtual element 700 may include any graphical elementsuitable for rendering or presentation on a display, including but notlimited to virtual objects associated with VR or AR experiences, gamepieces related to a gaming experience, graphical elements such as icons,thumbnails, taskbars, and menu items, and selection control elementssuch as cursors, pointers, buttons, handles, and sliders; any of whichmay or may not be associated with a graphical user interface (GUI).

For example, FIG. 7 is a perspective illustration of an example physicalenvironment, as seen through a display (not shown), depicting virtualelements 700 presented near movable objects 610. A first virtual element700-1 (e.g., a standing figure) is presented near a first movable object610-1 (e.g., a round tabletop). Attached to the tabletop is a firstpulse transmitter 620-1. In this example, a single pulse transmitter620-1 attached to a known point, such as the center, along with theobject mesh 611 as described herein, is sufficient to calculate thecurrent object location 615 because a tabletop typically moves in asingle plane.

A second virtual element 700-2 (e.g., a hanging figure) is presentednear a second movable object 610-2 (e.g., a door). Attached to the dooris a pair of second pulse transmitters 620-2 a, 620-2 b and a compass640, either or both of which may be used to calculate the current objectlocation 615 of the door. The compass 640 may broadcast its own compasssignal or, in some implementations, the broadcast pulse is composed sothe data packet includes the compass data. The pair of transmitters620-2 a, 620-2 b and the compass 640 are sufficient to calculate thecurrent object location 615 (which includes both position andorientation) because the door is movable in two dimensions, relative toits hinges.

A third virtual element 700-3 (e.g., a seated figure) is presented neara third movable object 610-3 (e.g., a serving tray). Attached to thetray is a pair of third pulse transmitters 620-3 a, 620-3 b and anaccelerometer 650, both of which may be used to calculate the currentobject location 615 (position, orientation, and heading) of the tray.The accelerometer 650 may broadcast its own accelerometer signal or, insome implementations, the broadcast pulse is composed so the data packetincludes the accelerometer data. Data from the accelerometer 650provides information about the motion of the serving tray, which ismovable in three dimensions, through the environment, over time.

Both the eyewear device 100 and the movable objects 610 are free to movethrough the environment. The rendering application 920 continuallyupdates the display so that the virtual element 700 persistently appearsnear the movable object 610. For example, as shown in FIG. 8 , for avirtual element 700 (e.g., a seated figure) associated with a movableobject 610 (e.g., a handheld serving tray), the rendering application920 continually updates the display so the seated figure appears toremain on the serving tray as the serving tray moves, and with regard toany movement of the eyewear device 100 which supports the display 180B.

As the eyewear 100 or the movable object 610 moves, over time, theapparent size of the virtual element 700 changes, depending on itscurrent location 615 relative the eyewear location 902. In this aspect,the virtual element library 480 includes, for each virtual element 700,a desired size relative to the physical environment 600 (along with aplurality of image assets used during by the rendering application 920).In use, the rendering application presents the virtual element 700 at acurrent size based on the image assets, the desired size, and thecalculated current object location 615, such that the virtual element700 appears persistently at the desired size relative to the movableobject 610 as it moves through the physical environment.

In some example implementations, the pulse transmitter 620 includes apower supply (e.g., a battery), a pulse generator, a transmitter, anantenna, and a read-only memory (ROM) or a chip with read-writecapability. The ROM includes an object identifier or stock keeping unit(SKU) associated with the movable object, and a predefined object mesh611 (as shown near the round tabletop 610-1 in FIG. 7 ). The predefinedobject mesh 611 which includes one or more known dimensions associatedwith each movable object 610. The object mesh 611 may be generated andstored in one or more formats, to enable spatial reconstruction usingvarious computer vision and AR applications. The object mesh 611, forexample, may include a point cloud, a solid model (e.g., useful withcomputer-aided drawing or drafting (CAD) applications), a surface model,or a set of planar surfaces. For example, the predefined object mesh 611for the round tabletop 610-1 includes a diameter and a thickness. Inthis example, data about the object mesh 611 (stored in the ROM) isincluded in the broadcast pulse, so that the object location application910 utilizes the object mesh 611 in calculating the current objectionlocation 615. Points along the object mesh 611 may be used by therendering application 920 to place the virtual element 700 at aparticular location on the movable object 610.

In another example implementation, the predefined object mesh 611 isstored in the movable object database 490, along with the objectidentifier or stock keeping unit (SKU) associated with the movableobject.

As shown in FIG. 7 , the example tracking and display system 400 mayinclude a static mesh 605 associated with the physical environment 600.A portion of the static mesh 605 is shown near the door in FIG. 7 . Inuse, the static mesh 605 includes dimensions associated with a pluralityof stationary objects located in the physical environment, including thewalls, floors, ceiling, and structures and features that are fixed orstationary. The rendering application 920 presents the virtual elements700 relative to the stationary objects as described and stored in thestatic mesh 605. In this aspect, the rendering application 920 utilizesthe static mesh 605 to establish a display priority for the virtualelements 700 and the movable objects 610, so that the objects nearestthe eyewear 100 are displayed in the foreground, and the objects orportions of objects further away are displayed in the background. Forexample, a stationary object defined in the static mesh 605 (e.g., acolumn) is utilized by the rendering application 920 to selectivelyobscure all or part of a virtual element 700 when the column is locatedin the foreground, between the virtual element 700 and the eyewear 100.

In another aspect, the static mesh 605 is utilized to establish a map ofthe fixed environment, without the need for a tracking application(e.g., a SLAM algorithm) to continuously scan and map the fixedenvironment.

In some implementations, the tracking and display system 400 cooperateswith a tracking application that is configured to track moving items,such as people and objects which are not attached to a pulsetransmitter. In this example, the tracking application is limited totracking only those moving items which are not attached to a pulsetransmitter and not registered and stored in the movable object database490. In other words, real-time scanning and tracking of the static mesh605 and those movable objects 610 defined by an object mesh 611 isdisabled, conserving computing resources without sacrificing precisionlocation and tracking.

In this example, a camera system coupled to the eyewear device 100captures frames of video data as the eyewear moves through the physicalenvironment. The tracking application is synchronized in time with theUWB receivers 680 and with the object location application 910; andsynchronized in space relative to the physical environment. The camerasystem, in some implementations, includes one or more high-resolution,digital cameras equipped with a CMOS image sensor capable of capturinghigh-definition still images and high-definition video at relativelyhigh frame rates (e.g., thirty frames per second or more). Each frame ofdigital video includes depth information for a plurality of pixels inthe image. In this aspect, the camera operates as a high-definitionscanner by capturing a detailed input image of the physical environment.The camera, in some implementations, includes a pair of high-resolutiondigital cameras 114A, 114B coupled to the eyewear device 100 and spacedapart to acquire a left-camera raw image and a right-camera raw image,as described herein. When combined, the raw images form an input imagethat includes a matrix of three-dimensional pixel locations. Thetracking application analyzes captured frames of video data andidentifies one or more moving items in the physical environment relativeto the static mesh 605. Using the locations of the identified movingitems, the rendering application 920 presents the virtual element 700 onthe display relative to the identified moving items.

Any of the functionality described herein for the eyewear device 100,the mobile device 401, and the server system 498 can be embodied in oneor more computer software applications or sets of programminginstructions, as described herein. According to some examples,“function,” “functions,” “application,” “applications,” “instruction,”“instructions,” or “programming” are program(s) that execute functionsdefined in the programs. Various programming languages can be employedto develop one or more of the applications, structured in a variety ofmanners, such as object-oriented programming languages (e.g.,Objective-C, Java, or C++) or procedural programming languages (e.g., Cor assembly language). In a specific example, a third-party application(e.g., an application developed using the ANDROID™ or IOS™ softwaredevelopment kit (SDK) by an entity other than the vendor of theparticular platform) may include mobile software running on a mobileoperating system such as IOS™, ANDROID™, WINDOWS® Phone, or anothermobile operating system. In this example, the third-party applicationcan invoke API calls provided by the operating system to facilitatefunctionality described herein.

Hence, a machine-readable medium may take many forms of tangible storagemedium. Non-volatile storage media include, for example, optical ormagnetic disks, such as any of the storage devices in any computerdevices or the like, such as may be used to implement the client device,media gateway, transcoder, etc. shown in the drawings. Volatile storagemedia include dynamic memory, such as main memory of such a computerplatform. Tangible transmission media include coaxial cables; copperwire and fiber optics, including the wires that comprise a bus within acomputer system. Carrier-wave transmission media may take the form ofelectric or electromagnetic signals, or acoustic or light waves such asthose generated during radio frequency (RF) and infrared (IR) datacommunications. Common forms of computer-readable media thereforeinclude for example: a floppy disk, a flexible disk, hard disk, magnetictape, any other magnetic medium, a CD-ROM, DVD or DVD-ROM, any otheroptical medium, punch cards paper tape, any other physical storagemedium with patterns of holes, a RAM, a PROM and EPROM, a FLASH-EPROM,any other memory chip or cartridge, a carrier wave transporting data orinstructions, cables or links transporting such a carrier wave, or anyother medium from which a computer may read programming code or data.Many of these forms of computer readable media may be involved incarrying one or more sequences of one or more instructions to aprocessor for execution.

Except as stated immediately above, nothing that has been stated orillustrated is intended or should be interpreted to cause a dedicationof any component, step, feature, object, benefit, advantage, orequivalent to the public, regardless of whether it is or is not recitedin the claims.

It will be understood that the terms and expressions used herein havethe ordinary meaning as is accorded to such terms and expressions withrespect to their corresponding respective areas of inquiry and studyexcept where specific meanings have otherwise been set forth herein.Relational terms such as first and second and the like may be usedsolely to distinguish one entity or action from another withoutnecessarily requiring or implying any actual such relationship or orderbetween such entities or actions. The terms “comprises,” “comprising,”“includes,” “including,” or any other variation thereof, are intended tocover a non-exclusive inclusion, such that a process, method, article,or apparatus that comprises or includes a list of elements or steps doesnot include only those elements or steps but may include other elementsor steps not expressly listed or inherent to such process, method,article, or apparatus. An element preceded by “a” or “an” does not,without further constraints, preclude the existence of additionalidentical elements in the process, method, article, or apparatus thatcomprises the element.

Unless otherwise stated, any and all measurements, values, ratings,positions, magnitudes, sizes, and other specifications that are setforth in this specification, including in the claims that follow, areapproximate, not exact. Such amounts are intended to have a reasonablerange that is consistent with the functions to which they relate andwith what is customary in the art to which they pertain. For example,unless expressly stated otherwise, a parameter value or the like mayvary by as much as plus or minus ten percent from the stated amount orrange.

In addition, in the foregoing Detailed Description, it can be seen thatvarious features are grouped together in various examples for thepurpose of streamlining the disclosure. This method of disclosure is notto be interpreted as reflecting an intention that the claimed examplesrequire more features than are expressly recited in each claim. Rather,as the following claims reflect, the subject matter to be protected liesin less than all features of any single disclosed example. Thus, thefollowing claims are hereby incorporated into the Detailed Description,with each claim standing on its own as a separately claimed subjectmatter.

While the foregoing has described what are considered to be the bestmode and other examples, it is understood that various modifications maybe made therein and that the subject matter disclosed herein may beimplemented in various forms and examples, and that they may be appliedin numerous applications, only some of which have been described herein.It is intended by the following claims to claim any and allmodifications and variations that fall within the true scope of thepresent concepts.

What is claimed is:
 1. A system for displaying a virtual element,comprising: a transmitter configured to couple with a movable objectassociated with a current object location in a physical environment andto broadcast a pulse, wherein the pulse comprises a unique identifierand a predefined object mesh associated with the movable object, andwherein the current object location is based on the pulse; an eyeweardevice comprising a localization application, a rendering application,and a display, wherein a current eyewear location is estimated by thelocalization application; and a virtual element presented by therendering application on the display at a virtual element location as anoverlay relative to the predefined object mesh, wherein the virtualelement location is based on the current object location and the currenteyewear location.
 2. The system of claim 1, wherein the predefinedobject mesh comprises known dimensions associated with the movableobject.
 3. The system of claim 1, further comprising: a static meshcomprising dimensions associated with a plurality of stationary objectslocated in the physical environment, wherein the rendering applicationpresents the virtual element in accordance with the static mesh.
 4. Thesystem of claim 3, further comprising: a camera coupled to the eyeweardevice and configured to capture frames of video data of the physicalenvironment; and a tracking application configured to identify, in thecaptured frames of video data, a plurality of moving items in thephysical environment relative to the static mesh, wherein the renderingapplication presents the virtual element on the display relative to theidentified plurality of moving items.
 5. The system of claim 1, furthercomprising: at least two synchronized receivers located at fixedreceiver locations relative to the physical environment, wherein thereceivers are in paired communication with the eyewear device, andwherein the receivers calculate the current object location based on thebroadcast pulse.
 6. The system of claim 1, wherein the transmittercomprises an ultra-wideband pulse transmitter comprising a power supply,a pulse generator, a transmitter, an antenna, and a read-only memory,wherein the unique identifier is stored in the read-only memory, whereinthe predefined object mesh is stored in the read-only memory, whereinthe pulse generator composes the pulse, and wherein the transmitterbroadcasts the pulse.
 7. The system of claim 1, further comprising: acompass coupled to the movable object and configured to broadcast acompass signal, wherein the current object location is based on thebroadcast compass signal; and an accelerometer coupled to the movableobject and configured to broadcast an accelerometer signal, wherein thecurrent object location is based on the broadcast accelerometer signal.8. The system of claim 1, wherein the current object location comprisesa current object position and a current object orientation relative tothe physical environment, the system further comprising: a secondtransmitter coupled to the movable object at a known distance from thetransmitter and configured to broadcast a second pulse, wherein thecurrent object orientation is based on the broadcast second pulse. 9.The system of claim 1, further comprising: a virtual element librarycomprising, for each of a plurality of virtual elements, a plurality ofimage assets and a desired size relative to the physical environment,wherein the rendering application presents the virtual element at acurrent size based on the image assets, the desired size, and thecurrent object location, such that the virtual element appearspersistently at the desired size relative to the physical environment.10. The system of claim 1, further comprising: a movable object databasecomprising, for each of a plurality of movable objects, a uniqueidentifier and a predefined object mesh.
 11. A method of displaying avirtual element, comprising: receiving a pulse broadcast by atransmitter configured to couple with a movable object in a physicalenvironment, wherein the pulse comprises a unique identifier and apredefined object mesh associated with the movable object; calculating acurrent object location associated with the movable object based on thepulse; estimating a current eyewear location associated with an eyeweardevice, the eyewear device comprising a display; and presenting on thedisplay at a virtual element location a virtual element as an overlayrelative to the predefined object mesh, wherein the virtual elementlocation is based on the current object location and the current eyewearlocation.
 12. The method of claim 11, wherein the predefined object meshcomprises known dimensions associated with the movable object, andwherein presenting the virtual element further comprises presenting thevirtual element in accordance with a static mesh comprising dimensionsassociated with a plurality of stationary objects located in thephysical environment.
 13. The method of claim 12, further comprising:capturing frames of video data of the physical environment using acamera coupled to the eyewear device; and identifying a plurality ofmoving items in the physical environment relative to the static mesh,wherein presenting the virtual element further comprises presenting thevirtual element on the display relative to the identified plurality ofmoving items.
 14. The method of claim 11, further comprising: pairingwith the eyewear device at least two synchronized receivers located atfixed receiver locations relative to the physical environment, whereinthe receivers calculate the current object location.
 15. The method ofclaim 11, wherein the transmitter comprises an ultra-wideband pulsetransmitter comprising a power supply, a pulse generator, a transmitter,an antenna, and a read-only memory storing the unique identifier and thepredefined object mesh, the method further comprising: generating thepulse using the pulse generator; and broadcasting the pulse using thetransmitter.
 16. The method of claim 11, wherein calculating the currentobject location further comprises: receiving a compass signal broadcastfrom a compass coupled to the movable object; and receiving anaccelerometer signal from an accelerometer coupled to the movableobject, wherein the current object location is based on at least one ofthe broadcast compass signal and the broadcast accelerometer signal. 17.The method of claim 11, wherein the current object location comprises acurrent object position and a current object orientation relative to thephysical environment, the method further comprising: estimating thecurrent object orientation is based on a second pulse broadcast from asecond transmitter coupled to the movable object at a known distancefrom the transmitter.
 18. The method of claim 11, wherein presenting thevirtual element further comprises: retrieving the virtual element from avirtual element library comprising, for each of a plurality of virtualelements, a plurality of image assets and a desired size relative to thephysical environment; rendering the virtual element at a current sizebased on the image assets, the desired size, and the current objectlocation, such that the virtual element appears persistently at thedesired size relative to the physical environment.
 19. A non-transitorycomputer-readable medium storing program code which, when executed, isoperative to cause an electronic processor to steps, the stepsincluding: receiving a pulse broadcast by a transmitter configured tocouple with a movable object in a physical environment, wherein thepulse comprises a unique identifier and a predefined object meshassociated with the movable object; calculating a current objectlocation associated with the movable object based on the pulse;estimating a current eyewear location associated with an eyewear device,the eyewear device comprising a display; and presenting on the displayat a virtual element location a virtual element as an overlay relativeto the predefined object mesh, wherein the virtual element location isbased on the current object location and the current eyewear location.20. The non-transitory computer-readable medium storing program code ofclaim 19, wherein the program code, when executed, is operative to causethe electronic processor to perform the steps of: presenting the virtualelement in accordance with a static mesh comprising dimensionsassociated with a plurality of stationary objects located in thephysical environment; capturing frames of video data of the physicalenvironment using a camera coupled to the eyewear device; andidentifying a plurality of moving items in the physical environmentrelative to the static mesh, wherein presenting the virtual elementfurther comprises presenting the virtual element on the display relativeto the identified plurality of moving items.